This invention relates generally to headers for crop-harvesting machines, and more particularly to an auger header connectable to the forward end of a specialized tractor, thereby forming what is generally know in the agricultural business as a swather or windrower. Even more particularly, the instant invention relates to the use of a slip clutch in the drive system of the auger of crop-harvesting header that allows, upon plugging of the auger, the drive to continue while the auger stops or slows. When the drive is reversed to back out the slug, a ratchet wheel on the auger drive shaft positively powers the auger in reverse, not allowing the clutch to slip.
In modern agriculture, especially in regard to harvesting forage crops, it is the present tendency to cut a relatively wide swath of the crop within a range of anywhere between 10 and 16 or more feet in width, and then consolidate the crop into a narrower, substantially continuous windrow, in which form the crop is left to dry in the field until the moisture content has been reduced to a value suitable for subsequent harvesting operations such as baling. The arranging of the crop into a continuous windrow around the field primarily is to facilitate the baling thereof.
Many older swather or windrower implements employed endless draper conveyors for purposes of consolidating a relatively wide swath of cut material into a narrower band thereof and then discharged onto the field as a windrow. Such devices offer various types of difficulties in that, as is well known, endless conveyors in agricultural equipment gradually stretch and also are subject to rather rapid wear, especially if carelessly used.
The more recent designs of windrower headers employ a consolidating auger operationally behind a cutterhead and rotating reel to receive the cut crop material and convey it centrally of the header from either lateral end portion thereof for feeding into a crop-conditioning mechanism, conditioning rolls, for instance. A header of this type is shown and described in U.S. Pat. No. 3,324,639 issued to L. M. Halls et al. on Jun. 13, 1967. A major problem encountered by such machines relates to plugging. Crop materials, weeds, and combinations thereof sometimes form into balls or tight seemingly large wads, known as slugs, that do not conveniently feed through and along the auger. One way to address this issue is to employ a floating auger, such as shown in the above-identified ""639 patent or in U.S. Pat. No. 4,296,592 issued to Irwin D. Mcllwain on Oct. 27, 1981. The floating auger is generally free to move vertically, thus allowing most slugs a better opportunity to follow the auger to the central consolidating area.
It would be helpful to have a drive system of the general type herein described with a simpler and more reliable mechanism for handling the slugs that are inevitably encountered during field operations. The instant invention provides such an alternative.
Accordingly, one object of the present invention is to provide an alternative mechanism for ejecting or extracting slugs from the auger of a crop-arvesting header.
Another object of the present invention is to provide a novel drive mechanism for the auger of a crop-harvesting header including a slip clutch to prevent damage from slugs and to provide a positive reverse drive to either eject slugs or push them into a position for extraction.
It is another object of the instant invention to provide a drive mechanism for the auger of a crop-harvesting header including a slip clutch with friction discs to allow the main drive to continue to turn while the auger either stops or slows.
Yet another object of the present invention is to provide a drive mechanism for the auger of a crop-harvesting header including pawls on the auger sprocket to engage a ratchet wheel on the auger drive shaft to positively drive the auger in the reverse direction when ejecting slugs.
It is yet another object of this invention to provide an improved drive mechanism for the auger of a crop-harvesting header which is durable in construction, inexpensive to manufacture, carefree of maintenance, facile in assemblage, and simple and effective in use.
It is a still further object of the instant invention to provide a drive system for the auger of a crop-harvesting header that includes a slip clutch to slow or stop auger rotation upon encountering a slug or foreign object of sufficient size, and pawls on the drive sprocket that engage a ratchet wheel on the auger drive shaft when the drive is reversed to provide positive power to the auger in reverse to eject the obstruction.